Etaoin shrdlu (//) is a nonsense phrase that sometimes appeared in print in the days of "hot type" publishing because of a custom of type-casting machine operators. It appeared often enough to become part of newspaper lore.
The letters on type-casting machine keyboards (such as Linotype and Intertype) were arranged by letter frequency, so e-t-a-o-i-n s-h-r-d-l-u were the lowercase keys in the first two vertical columns on the left side of the keyboard. When an operator made a mistake in composing, he would often finish the line by running his finger down the first two rows of the keyboard and then start over. Occasionally the faulty line of hot-metal type would be overlooked and be printed erroneously. This happened often enough for "etaoin shrdlu" to be listed in the Oxford English Dictionary and in the Random House Webster's Unabridged Dictionary.
In the early days of computer studies of language, an examination of newspaper text and television news copy included a letter frequency count, followed by a journal article. Irving Fang concluded that the linotype machines got it nearly right, but that the actual frequency of letters in the English language is ETAONI RSHDLC.
Appearance outside typography
The phrase has gained enough notability to appear outside typography, including:
- SHRDLU was used in 1972 by Terry Winograd as the name for an early artificial-intelligence system in Lisp.
- The ETAOIN SHRDLU Chess Program was written by Garth Courtois Jr. for the Nova 1200 mini-computer, competing in the 6th and 7th ACM North American Computer Chess Championship 1975 and 1976.
- Etaoin Shrdlu, or a portion of the phrase, is a character in works of fiction, including: Elmer Rice's 1923 play The Adding Machine.
- In 1942 Etaoin Shrdlu was the title of a short story by Fredric Brown about a sentient Linotype machine. (A sequel, Son of Etaoin Shrdlu: More Adventures in Typer and Space, was written by others in 1981.)
- Anthony Armstrong's 1945 whimsical short story "Etaoin and Shrdlu" ends "And Sir Etaoin and Shrdlu married and lived so happily ever after that whenever you come across Etaoin's name even today it's generally followed by Shrdlu's".
- the name of a science fiction fanzine edited by Sheldon Lee Glashow & Steven Weinberg
- "etaoin shrdlu". Merriam-Webster. Encyclopædia Britannica.
- Stoddard, Samuel (2004). "Letter Frequency". Fun With Words. RinkWorks. Retrieved 28 June 2013.
- Farewell, Etaoin Shrdlu (Motion picture). New York City: Educational Media Collection/University of Washington. Retrieved 28 June 2013.
- Irving E. Fang, "It Isn't ETAOIN SHRDLU; It's ETAONI RSHDLC," Journalism Quarterly, December 1966, vol. 43, no. 4, pages 761-762
- Peter Norvig "English Letter Frequency Counts: Mayzner Revisited or ETAOIN SRHLDCU"
- Winograd, Terry. "How SHRDLU got its name". SHRDLU. Stanford University. Retrieved 28 June 2013.
- Courtois Jr., Garth (7 August 2008). "Am I old enough to remember keypunch cards? Umm, yeah...". Blog Archives. ababsurdo.com. Retrieved 27 June 2013.
- Quinion, Michael. "etaoin shrdlu". Weird Words. World Wide Words. Retrieved 28 June 2013.
- "Old Legends", Gregory Benford
- Farewell, Etaoin Shrdlu at the Internet Movie Database
- "What's the origin of the mysterious phrase etaoin shrdlu?" at The Straight Dope
- Excerpt demonstrating etaoin shrdlu from the film Linotype: The Film at the Internet Movie Database
- Over 100 examples of the phrase used in American newspapers from 1836–1922 at the Library of Congress
- English Letter Frequency Counts: Mayzner Revisited or ETAOIN SRHLDCU